1. Poisoning in an intensive care unit: 8 years experience
Dr Grace SM Lam
Department of Intensive Care
Toxicology Meeting
7 August 2009

2. introduction Poisoning Knowledge of local poisoning pattern
A significant cause of morbidity & mortality worldwide, and a common cause of ICU admission.
A heterogeneous subject that poses a challenge for clinicians.
Knowledge of local poisoning pattern
Guide focus of poisoning prevention;
Guide clinical research & professional training;
Improve management of patients with poisoning.

3. Aims of study To describe:
Pattern of poisoning
Clinical characteristics
Outcomes
Of patients admitted to the ICU for poisoning

4. methods The study included patients:
Admitted to PYNEH ICU
From 1 January 2000 – 31 May 2008
For poisoning, defined as exposure to:
An agent capable of producing a deleterious response in an individual; or
A drug at a dosage exceeding that normally used for human in the prophylaxis, diagnosis or therapy of disease
Significant head injury after intoxication & fire victims were excluded

5. results 7796 Total ICU admissions during the study period
279 admissions identified using the inclusion criteria
265 further analyzed (3.4% total ICU admission)
14 excluded:
10 chronic alcoholics /drug addicts with significant HI
4 fire victims with CO poisoning

6. Demographic & clinical characteristics
All patients (N=265)
CO poisoning (N=40)
TCA poisoning (N=46)
Age (years; median, IQR)
38 (30-49)
36 (30-42)
35 (29-46)
Female
144 (54.3%)
17 (42.5%)
30 (65.2%)
Charlson’s Comorbidity score ≥1
219 (82.6%)
46 (17.4%)
39 (97.5%)
1 (2.5%)
38 (82.6%)
8 (17.4%)
Presence of psychiatric illness
Depression
Schizophrenia and related disorder
127 (47.9%)
75 (59.1%)
15 (11.8%)
14 (35%)
5 (35.7%)
1 (7.1%)
37 (80.4%)
27 (73.0%)
2 (5.4%)
Previous suicidal attempt
87 (32.8%)
15 (37.5%)
20 (43.5%)
Intent
Suicide
Recreation
Accident
Homicide
225 (84.9%)
33 (12.5%)
5 (1.9%)
2 (0.8%)
40 (100%)
46 (100%)
Time to AED presentation (hours; median, IQR)
(N=169)
2 (1-5)
(N=21)
5 (1-8.5)
(N=39)
2 (1-4)
Physiological parameters on presentation (median, IQR)
Glasgow coma scale
Mean arterial pressure (mmHg)
9 (4-14)
88 (78-100)
8 (5-11)
86 (78-99)
10 (6-14)
91 (84-99)
Initial blood results (median, IQR)
Creatine Kinase (mmol/L)
COHb (%)
129 (66-390)
---
368 ( )
28.4 ( )
87 (48-197)
APACHE II score (median, IQR)
15 (9-19.5)
17 (11-21)
15 (9-19)

7. Pattern of poisoning Miscellaneous Theophylline Bricanyl durule
Agent
Number (%)
Sedatives
Benzodiazepines
Zopidem & Zopiclone
Phenobarbital
Others
67 (25.3%)
31 (11.7%)
4 (1.5%)
11 (4.1%)
Alcohol
61 (23.0%)
Antidepressant
TCA
SSRI
Lithium
46 (17.4%)
13 (4.9%)
2 (0.8%)
9 (3.4%)
Carbon monoxide
40 (15.1%)
Antipsychotics
29 (10.9%)
Drugs of abuse
CNS depressants
CNS stimulants
18 (6.8%)
10 (3.8%)
Analgesics
Paracetamol
Dologesic
Salicylate
NSAIDS
5 (1.9%)
6 (2.3%)
3 (1.1%)
Anti-histamines
Household products
Dettol
8 (3.0%)
Anti-hypertensives
Beta-blockers
CCB
Organophosphate
Tetramine
Miscellaneous
35 (13.2%)
Unknown
Miscellaneous
Theophylline
Bricanyl durule
Anti-epileptic agents
Hypoglycemic agents
Artane
Allopurinol
Warfarin
Commercial slimming agent
Thinner

8. Mortality 8 (3%) did not survive to hospital discharge
5 (1.9%) died in ICU
Age (years)
Sex
Agent(s) used
Treatments
Survival from presentation (Days)
Cause of death 61 M
Thinner, Paracetamol
Ventilation, Vasopressor, CVVH 1
Multi-organ failure 39
Carbon monoxide
CPR, Ventilation, Vasopressor
Hypoxic encephalopathy, Brainstem death 26 F
Dothiepin, Paracetamol
CPR, Ventilation, MDAC 2
Cardiac arrest on arrival 29
Amphetamine, Tripolidine, Alcohol
Ventilation, 3
Cerebral oedema 53
Lithium, Chlorpromazine, Alcohol
Ventilation, Vasopressor, Gastric lavage, MDAC, CVVH 5 33
Amphetamine, Ketamine
Ventilation, Tracheostomy 75
Nosocomial pneumonia 65
Dothiepin, Metformin, Glibenclamide
MDAC
170 46
Phenobarbital
Ventilation
1877
Nosocomial sepsis

9. Complications Complication All (N=265) CO (N=40) TCA (N=46)
Rhabdomyolysis
Acute renal failure
Adverse cardiac events
Shock
Seizure
Aspiration pneumonia
Delayed neurological sequelae
28 (10.6%)
10 (3.7%)
15 (5.7%)
21 (7.9%)
23 (8.7%)
31 (11.7%)
---
10 (25.0%)
1 (2.5%)
2 (5.0%)
8 (20.0%)
3 (7.5%)
4 (8.7%)
1 (2.2%)
3 (6.5%)
5 (10.9%)
7 (15.2%)

10. Duration of mechanical ventilation
67.9% intubated and mechanically ventilated
65.3% with GCS ≤8 on presentation
Median = 1 day
Independent predictors of a duration of mechanical ventilation > 1 day:
Odds ratio (95% Confidence interval)
P value
Rhabdomyolysis
Aspiration pneumonia
APACHE II ≥25
5.20 (1.29 – 20.99)
4.43 (1.53 – 12.83)
3.54 (1.24 – 10.07)
0.021
0.006
0.018

11. ICU Length of stay Median = 1 day
Independent predictors of an ICU LOS >1 day:
Odds ratio (95% CI)
P value
Rhabdomyolysis
Aspiration pneumonia
Shock
Age >65 years
APACHE II score ≥25
Alcohol intoxication
12.18 (3.07 – 4.88)
9.25 (2.70 – 31.73)
6.19 (1.33 – 28.88)
4.95 (1.52 – 16.13)
3.69 (1.19 – 11.46)
0.22 (0.07 – 0.66)
<0.001
0.020
0.008
0.024
0.007

12. Acute HOSPITAL length of stay
Median = 3 days
Independent predictors of an acute hospital LOS >3 days:
Odds ratio (95% CI)
P value
Age >65 years
Aspiration pneumonia
Presence of comorbidity
Alcohol intoxication
6.64 (1.40 – 31.44)
5.34 (1.39 – 20.50)
4 (1.67 – 9.57)
0.36 (0.18 – 0.75)
0.017
0.015
0.002
0.006

13. result CO poisoning: HBO performed in 2 (5%) patients
No factor was identified as independent predictors of neurological or cardiac complications
Including initial COHb level

14. result
TCA poisoning
No factor was identified as independent predictors of neurological or cardiac complications
Complications
No. (%)
QRS duration
QTC duration
RaVR
R/SaVR
<0.1s
≥0.1s
<0.44s
≥0.44s
<3mm
≥3mm
<0.7
≥0.7
Cardiac sequelae
Absent
Present
P value
26 (96.3) 13 (81.3)
1 (3.7) (18.8)
0.137
18 (100) 21 (84)
0 (0) (16)
0.127
25 (86.2) 14 (100)
4 (13.8) 0
0.286
30 (88.2) 9 (100)
4 (11.8)
0.564
Seizure
26 (96.3) 12 (75)
1 (3.7) (25)
0.056
17 (94.4) 21 (84)
1 (5.6) (16)
0.380
26 (89.7) 12 (85.7)
3 (10.3) (14.3)
1.00
30 (88.2) 8 (88.9)
4 (11.8) (11.1)
Combined
25 (92.6) (68.8)
2 (7.4) (31.3)
0.820
17 (94.4) (76)
1 (5.6) (24)
0.209
24 (82.8) 12 (85.7)
5 (17.2) (14.3)
28 (82.4) (88.9)
6 (17.6) (11.1)

15. limitations Retrospective study ICU admission was not standardized
Missing data e.g. time of intoxication
ICU admission was not standardized
Heterogeneous study population & uncommon adverse outcomes limited the validity of statistical analyses
Long-term outcome was not systematically studied
Single-center study

16. conclusions
The 4 commonest poisons encountered in our ICU from 2000 to 2008 were BDZ, alcohol, TCA, and CO
Mortality was comparable to international data
Timely management with emphasis on prevention of aspiration pneumonia may reduce adverse outcomes
It is hoped that outcomes of these patients can be further improved in the future through:
Collaboration with local advisory bodies (HKPIC)
Raising clinicians’ awareness
Continued efforts on clinical trials